Vacuum cleaner



March 14, 1967 T. BRIMBERG 3,308,603

I VACUUM CLEANER Filed May 17, 1965 4 Sheets-Sheet 1 INVENTOR.

March 14, 1967 Filed May l7, 1965- T. BRIMBERG VACUUM CLEANER 4 Sheets-Sheet 2 March 14, 1967 T. BRIMBERG VACUUM CLEANER 4 Sheets-Sheet 3 Filed May 17, 1965 March 14, 1967 T. BRIMBERG VACUUM CLEANER Filed May 17. 1965 4 Sheets-Sheet 4 INVENTQR W BY v fiwlrrrofi/vsy 3,308,608 VACUUM CLEANER Torsten Brimberg, Bandhagen, Sweden, assignor to Aktiebolaget Electrolux, Stockholm, Sweden, a corporation of Sweden Filed May 17, 1965, Ser. No. 456,144 Claims priority, application Sweden, Jan. 28, 1960,

815/60 Claims. (Cl. 55-276) This application is a continuation-in-part of application Ser. No. 85,305, filed Jan. 27, 1961, now abandoned.

The present invention relates to vacuum cleaners, and is particularly directed to improvements in portable vacuum cleaners.

An object of the invention is to provide an improved vacuum cleaner of the described character in which the housing is of light-weight construction so as to contribute to the portability thereof, and wherein the housing further has advantageous vibration-damping and soundproofing or sound absorbing characteristics.

In-accordance with the invention, the housing of the vacuum cleaner is in the form of a body of foamed, semirigid plastic, for example, foamed polystyrene or polyurethane, having communicating compartments therein for accommodating the motor-fan unit and the dust collector or separator, respectively, with the outer surface of the foamed plastic body being covered by a layer of elastomeric material to resist damage to the foamed plastic body when the latter is subjected to impacts, as well as to avoid scratching or marring of furniture, walls or the like with which the housing is inadvertently contacted.

The above, and other objects, features and advantages of the invention, will be apparent in the following detailed description of an illustrative embodiment thereof which is to be read in connection with the accompanying drawings forming a part hereof, and wherein:

FIG. 1 is a side elevational view of a vacuum cleaner embodying the present invention and shown supported by a carrying harness to be used in mounting the vacuum cleaner on the users back;

FIG. 2 is a vertical, transverse sectional view of the vacuum cleaner appearing in FIG. 1, the air moving means or motor-fan unit 26, which is diagrammatically i1- lustrated, being partly broken. away and in section;

FIG. 3 is a front elevational view of the vacuum cleaner of FIGS. 1 and 2, but with the latter shown standing on one end thereof either for use as a floor-supported appliance or during storage;

FIG. 4 is a vertical sectional view of a vacuum cleaner like that shown in FIGS. 1 to 3 illustrating another embodiment of the invention;

FIG. 5 is an exploded perspective view of parts of the vacuum cleaner shown in FIG. 4 to illustrate details more clearly;

FIG. 6 is an enlarged fragmentary sectional view of parts shown in FIG. 4; and FIG. 7 is an enlarged fragmentary sectional view taken at line 7-7 of FIG. 5 when the exploded parts thereof are assembled in the manner illustrated in FIG. 4.

Referring to the drawings in detail, it will be seen that the illustrated vacuum cleaner embodying the invention includes a housing 10 made up of a generally rectangular body 11 (FIG. 2) which is preferably molded of foamed, semi-rigid plastic, for example, foamed cellular polystyrene or polyurethane. The outer surface of foamed plastic body 11 is covered with a layer 12 of shock absorbing or resistant elastomeric material, such as, for example, polyvinyl chloride, natural or synthetic rubber or the like, so that the layer 12 protects the body 11 from damage when the latter is subjected to impacts and further avoids scratching or marring of furniture or wall United States Patent 0 Patented Mar. 14, 1967 surfaces in the event of inadvertent contact of the housing 10 therewith.

As is apparent in FIG. 1, the housing 10 has rounded top and bottom surfaces 13 and 14, respectively, and a flat back surface 15 extending therebetween and on which the housing 10 can slide when it is desired to use the vacuum cleaner as a floor supported appliance. If desired, the back surface 15 may be provided with metal slides or skids 15a to facilitate the sliding movement of the housing over a supporting floor surface. The front surface 16 of housing 10 is concave so that, when the housing 10 is supported on the users back indicated schematically by the broken line 17 on FIG. 1, the concave front sur-' face 16 conforms comfortably to the contours of the users back.

In order to support the housing 10 on the users back, as normally intended when the vacuum cleaner is used as a portable appliance, support pads 18 (FIGS. 1 and 3) extend from the front of the housing adjacent the top and bottom thereof, and metal rings or loops 19 embedded in the plastic of housing 10 during molding of the latter extend from the upper support pads 18 and provide fittings for attachment to straps 20 intended to extend around the shoulders of the user and forming a harness for support of the housing.

As shown in FIG. 2, the body 11 of housing 10 is formed with parallel, substantially coextensive internal compartments or spaces 21 and 22, and a duct 23 extending between the compartments at one end 11c and 110" of the body 11. As indicated schematically at 24, members of dust filtering material may be inserted in duct 23,

and the housing 10 may be further provided with a removable cover or cap 25 so as to afford access to duct 23.

The compartments 21 and 22 preferably extend laterally in housing 10, with the upper compartment 21 accommodating a motor-fan unit 26 and the lower compartment 22 receiving a dust collector or separator 27 in the form of a bag or sack of air-permeable material. The compartments 21 and 22 of foamed plastic body 11' are preferably provided with linings 28 and 29, respectively, of a relatively harder material, for example, a suitably rigid plastic or metal, and at least the lining 28 of compartment 21 is preferably provided with perforations 30 for a purpose hereinafter indicated in detail. Further, metal attachment members 31 and 32 are provided for mounting the motor-fan unit 26 within compartment 21, and such metal attachment members 31 and 32 may be conveniently anchored or embedded in, and thereby united to, the body 11 during the manufacture of the latter by injection molding.

As is apparent in FIG. 2, the upper and lower compartments 21 and 22 have their ends remote from duct 23 opening at a side surface 33 of the housing as at 34 and 35. The opening 34 of upper compartment 21 constitutes the air exhaust opening of the vacuum cleaner housing, and an air diffuser 36 formed, for example, of layers of porous fabric, is preferably mounted in such opening so as to difiuse the air under pressure issuing therefrom.

The suction side of motor-fan unit 26 communicates with duct 23 so that air is drawn through the latter fromcompartment 22 containing dust collector 27. Thus, the opening 35 of compartment 22 at the side 33 of housing 10 constitutes the suction opening of the housing, and a cap 37 is removably mounted in the suction opening 35 and rotatably carries a suction connection 38 to which the usual flexible suction hose 39 is suitably attached.

At the side 40 of housing 10 remote from side 33, there is provided a projection 41 having a cylindrical outer surface 42 and a flat end surface 43 so that, during storage of the vacuum cleaner, or during use of the latter as a floor-supported appliance, the housing 10 can stand on p the flat surface 43 and thereby occupy a relatively small floor area. Further, the outer cylindrical surface 42 of projection 41 can receive a reel 44 which is held on projection 41 by a spring detent device 45 (FIG. 2), and which is intended to have wound thereon the usual electric cord or cable 46 by which the motor of unit 26 is connected to a source of electricity. The reel 44 is of conventional design and can have the cord 46 unwound therefrom against a yieldable spring force so that, upon release of cord 46, the latter is automatically rewound on the reel.

The reel 44 can be removed from projection 41 and alternatively mounted on a support or suspension 47 therefor extending from one of the straps 20 at the front of the harness by which housing 10 is mounted on the users back. Thus, when the vacuum cleaner embodying the invention is used as a portable device, the reel 44 carrying the electric cord 46 is at the front of the user so as to facilitate unwinding and rewinding of the cord.

It will be understood that, when the vacuum cleaner is in use, conventional wand or pipe sections (not shown) are attached to the end of flexible hose 39 remote from the suction connection 38 and a suitably shaped nozzle or brush is, in turn, connected to such pipe section for cleaning rugs, floors or upholstery.

The described housing 10 of the vacuum cleaner embodying the invention has the advantage of being light in weight so as to facilitate the carrying thereof when the vacuum cleaner is used as a portable appliance. Further, by reason of the parallel arrangement of the compartments 21 and 22 accommodating the motor-fan unit 26 and the dust collector 27, respectively, with the motor-fan unit disposed above the dust collector, the housing 10 is compact, particularly in the lateral direction, so as to avoid any protrusion of the housing beyond the sides of the user on whose back the housing is supported. Since the suction connection 38 for the hose 39 extends from one side of the housing 10 adjacent the bottom of the latter, it is possible to use a hose 39 of relatively short length, which results in an improved suction effect at the cleaning nozzle.

The described construction of the housing 10 further has the advantage of providing a vibration-damping mounting for the motor-fan unit 26 which'is secured to the mounting members 31 and 32 embedded in the semirigid foamed plastic of body 11. The foamed plastic of body 11, particularly in combination with the elastomeric outer layer 12, provides an exceptionally effective soundproofing or absorbing construction. To begin with, the cellular nature of the foamed plastic of body 11 provides efiicient sound absorbing. Further, sound waves that are not initially absorbed by the foamed plastic body are reflected back into such body by the outer layer 12 of elastomeric and denser material so that the sound waves are gradually absorbed by the foamed plastic. The perforations 30 provided in the relatively rigid or harder lining 28 of compartment 21 permit the sound waves to enter the foamed plastic body 11, thereby avoiding reverberation of the sound within compartment 21.

The vibration damping and sound absorbing characteristics of housing 10 contribute greatly to the convenience and comfort with which such housing may be carried by the user during operation of the vacuum cleaner.

It will now be understood that the suction cleaner shown in FIG. 2 comprises a housing or casing 10 prvided with an air inlet connection 38 and an air outlet 34 and dirt collecting means 27 and air moving means 26 therebetween. The casing comprises a hollow semirigid cellular plastic body 11 having an inner wall 11a defining the elongated compartment or cavity 21 of cylindrical form and having an open end at 21a which is axially removed from and at the vicinity of the air outlet 34 and an internal shoulder 21b at its opposite end. The air moving means 26 comprises a motor-fan unit which is disposed in the cavity 21 and extends lengthwise thereof from the internal shoulder 21b to the open end at 21a at the one end of the cavity 21.

The motor-fan unit 26 is diagrammatically illustrated in FIG. 2 and includes a motor 26b and a fan 26a which is driven thereby. The motor 26b and fan 26w are provided with housings 26b and 26a, respectively, which are of cylindrical form and disposed in end-to-end relation and connected to one another at 260 in any manner well known in the vacuum cleaner art to provide the unitary motor-fan unit 26. Air flowing from the dust collector 27 passes through the duct 23 into the inlet 26a of the fan 26a, and, after passing through the motor 26b, is discharged through an air outlet end thereof through an opening in a member 81 and fiows through an air exhaust passageway 21c and is discharged through the air outlet 34.

In FIG. 2 the left end of the fan housing 26a" is mounted in position in the cellular plastic body by structure comprising first means 32 which functions to locate and position one end of the unitary motor-fan unit 26 against the internal shoulder 21b of the cavity 21 and second means 31 axially removed from the first means 32, which functions to locate and position the right end of the motor housing 26b" of the motor-fan unit 26 at 21a at the one or right end of the elongated lining 28 of the cavity 21 seen in FIG. 2.

The first and second means 3-2 and 31 of the mounting structure position the motor-fan unit 26 in the elongated cavity 21 with the inner Wall thereof spaced from the motor-fan unit between the one end at 21a at the open end of the lining 2 8 of the cavity 21 and the opposite end at the internal shoulder 21b. The motor-fan unit 26 is anchored against the internal shoulder 21b in the elongated cavity 21 by the apertured member 81 which overlies the right end of the motor 26b in FIG. 2 and bears against the second means 32 and is anchored thereto at 810. The plastic body in its entirety is referred to by the reference numeral 11 and includes integrally formed components 11b, 11b" and 11b'. The components 11b and 11b" define the compartment 21 and the components 11b" and 11b' define the compartment 22. The components 11b and 11b" collectively function as a supporting backbone for the motor-fan unit 26 between the first and second means 32 and 31 of the mounting structure and completely envelops the motor-fan unit from one end to the opposite end thereof and serves to mufiie sound and dampen variations produced by the motor-fan unit 26.

The lining 28 of the cavity 21 is apertured at 30 and in intimate physical contact with the inner wall 11a of the cellular plastic body 11 and formed of material of greater rigidity than that of the body 11. The first locating and positioning means 32 for the motor-fan unit 26 bears against the lining 28 at the internal shoulder 21b and the second locating and positioning means 31 for the motor-fan unit 26 is disposed in a plane transverse to the axis of the motor-fan unit 26 and intersects the open end of the lining 28 at 21a at the one or right end of the cavity 21 seen in FIG. 2.

The integrally formed components 11b" end 16b' of the plastic body 11 collectively provide the space 22 in which the dirt collecting means 27 is positioned, the cavity 21 and space 22 being disposed alongside one another. The cavity 21 and space 22 are connected by a passage 23 which is formed at least in part by the integrally formed components 11b, 11b", 11b, 11c and 110" of the plastic body 11 and is transverse to the longitudinal axes of the cavity 21 and the space 22 and is provided with filter means 24 which functions to absorb sound. The plastic body 11 is formed with an opening 110 at its exterior which is in communication with the passage 23 and closed by a removable cover 25, whereby thepassage 23 is accessible to insert and remove the filter means 24 into and from the passage 23.

It will now be understood that a suction cleaner has. been provided having a casing 10 provided with an air inlet 37 formed in an opening of the cap 37 and an air outlet 34. The casing comprises the body 11 having wall means 11b, 11b", 11b, 11c, 11c and cover 25 defining the U-shaped passageway 22, 23 and 21. The air flowing from the motor 26b passes through an exhaust passageway 210 in the arm or compartment 21 to the air outlet 34. The aforementioned wall means of the body 11 includes a dividing wall comprising the partition 11b" and cover 25 between the elongated arms 21 and 22 which has the opening or passageway 23 therein. The partition 11b" forms part of a unitary member or body 11 which is defined by body components 11b and 11b' and is of annular form and provides the Wall means 11b" and 1112" disposed about the dust bag compartment 22 in the arm 22 of the U-shaped passageway. The aforementioned wall means of the body 11 further includes the cap or wall member 37 which functions as a wall of the dust bag compartment 22 and is transverse to the lastmentioned member of annular form defined by the body components 11b" and 11b'. The wall member 37 has an opening 37 defining the air inlet of the cleaner. As clearly shown in FIG. 2, the aforementioned wall means 11b, 11b", 11b, 11c, 11c", cover 25 and cap 37, which define the U-shaped passageway, embody structure 11b, 11b" .and 11c for mounting the other arm 21 of the U on the. outside of the one arm 22 thereof.

Another embodiment of the invention is illustrated in FIGS. 4 to 7 in which parts similar to those shown in FIGS. 1 to 3 are designated by the same reference numerals to which 100 has been added. The vacuum cleaner of FIGS. 4 to 7 comprises a shell or housing 110 which includes an outer wall 112 and a pair of inner walls 128 and 129 of annular form and a body 111 of foamed plastic therebetween. Closure members 133 and 140 are provided at the top and bottom, respectively, of the housing 110.

The closure member 133, which is of the general shape shown in FIG. 5, is formed with a pair of openings 134 and 135 and may be referred to as an apertured closure member. As shown in FIG. 4, the closure member 133 includes an outer flange 133a which overlies and telescopically fits over the top side of the outer wall 112, a first inner flange 13317 of annular form which extends inward at the opening 134-, and a second inner flange 1330 of annular form which extends inward at the opening 135. The inner flanges 133 b and 133s telescopically fit within the top ends of the inner walls 128 and 129.

The apertured closure member 133 is formed with an outer ridge 133d which defines a recess 1332 having a flat bottom 133 and an upward sloping wall 133g. The ridge 133d further includes a top wall 133k connecting the outer flange 133a and the sloping Wall 1333. As seen in FIG. 4, portions of the bottom 133 of the recess 13-3e rest on the top ends of the inner walls 128 and 129 and the body 111 and projects radially inward at the openings 134 and 135 past the inner flanges 1331) and 1330.

The closure member 140, which is irnperforate, is generally like the apertured closure member 133 just described and includes an outer flange 140a which overlies and telescopically fits over the bottom side of the outer wall 112, a first inner flange 14Gb of annular form which extends inward at the bottom of the inner-wall 128, and a second inner flange 1400 of annular form which extends inward at the bottomof the inner Wall 129. The inner flanges 140 h and 1400 telescopically fit Within the bottom ends of the inner walls 128 and 129, respectively.

As shown in FIGS. 4 and 5, the ridge 140d of the imperforate closure member 140 is provided with spaced reinforcing ribs 140k between the outer flange 140a and the sloping wall 140g. The perforate member 133 also may be provided with spaced reinforcing ribs 133k between the outer flange 133 and the sloping wall 133g, as shown in Feb. 4. The closure members 133 and 140, which desirably may be formed of plastic, are essentially rigid and yet resilient to a certain extent to facilitate positioning them over the top and bottom sides of the outer wall 112 and inner Walls 128 and 129 to form airtight seals between the ends of the inner walls 128 and 129 and the inwardly directed flanges of the closure members.

To the top and bottom closure members 133 and are fixed backing plates 50 and 51, respectively, which may be formed of sheet metal. The top plate 50 is flat and formed with outwardly sloping sides or flanges 50a and 50b. The top plate 50 rests against the bottom 133 of the recess 133e and the flanges 50a and 50b bear against the outwardly sloping wall 133g. Similarly, the bottom plate 51 rests against the bottom surface of the member 140 of the recess 140e and the flanges 51a and 51!) thereof bear against the outwardly sloping wall 140g.

As shown in FIGS. 5 and 7, the inner walls 128 and 129 at their top ends are provided with angle members 52. The vertical arms of the angle members 52 are fixed at 5 3, as by riveting, for example, and the horizontal arms, which are flush with the top surface of the body 111 of foamed plastic, project radially outward from the inner walls 128 and 129 and are formed with threaded openings 5-4. The inner walls 128 and 129 at their bottom ends are provided with angle members 52' which are like the angle members 52 and flush with the bottom surface of the body 111 of foamed plastic.

The top closure member 1 33 and backing plate 50 resting thereon are fixed to the inner walls 128 and 129 by threaded cap screws 5-5. The threaded openings 54 in the angle members 52 receive the cap screws 55 which pass through aligned openings '56 and 57 in the backing plate 50 and closure member 133, respectively. In a similar manner the bottom closure member 140 and backing plate 51 are fixed to the inner walls 128 and 129 by threaded cap screws which are like the cap screws 55 and pass through aligned openings 56' and 57 in the bottom backing plate 51 and closure member 140, respectively, and threadingly engage the threaded openings 54 in the angle members 52'.

The inner wall 129 defines a compartment 122 in which a dust collector 127 is disposed. The dust collector 127 comprises an open-ended dust bag formed of cloth or paper which is permeable to air and includes a rim 127a at its open end to which a ring 1271) of resilient material such as rubber, for example, is fixed. When the dust bag 127 is positioned in the compartment 122 in the manner shown in FIG. 4, the resilient ring 12712 is held at the top side of the backing plate 50 about an opening 500 therein which is slightly smaller than the opening in the closure member 1 33 and in alignment therewith. The plate 50 is provided with a cover 13-7 which is hinged at 137a and formed with an air inlet opening 137]) to which a coupling of a suction hose may be detachably connected in a manner like that shown in FIG. 2 and described above.

The top backing plate 50 is provided with a catch 137a which cooperates :with a latch 137d provided on the cover 137 for holding the latter in its closed position. In such closed position the rim of the cover 137 at its underside bears against the resilient ring 12% and holds the latter against the top face of the backing plate 50 to provide an airtight seal between the cover 137 and the open end of the dust bag 127.

.A motor-fan unit 126 is disposed in a compartment1-21 defined by the inner wall "128. The motor-fan unit 126 includes a centrifugal fan 126a carried at one end of an electric motor 12Gb. The motor 12611 is connected by conductors 58 and 59 to an electric switch 60 which is removably fixed to the top backing plate 50 at an opening therein. The switch 60 is provided with an operating member 61 connected by an electric cord 62 to a source of electrical energy.

The motor-fan unit 1 26 is detachably mounted in position on the inner Wall 128 by structure like that described in US. Pat. No. 2,843,315 of Lars J. Faith- E11,

granted July 15, 1958. The mounting structure includes a stationary wall part 63 and an annular flange 64 carried by the motor 1126b. The wall part 63 is L-s'haped in section and fixed at 65, as by riveting, for example, to the inner wall 128, as shown in FIG. 6. The annular flange 64 and stationary wall part 63 coact to form a slip-clamp type of connection, suitable springs 66 and a resilient member 67 providing a resilient mounting for the motor-fan unit.

The resilient member 67 is of annular form and includes a U-shaped part or seal 68 in which snugly fits an outwardly extending flange 69 of a Zig-zag shaped shield 70 disposed about the electric motor 126]). One leg 7'1 of the U-shaped part 68 of the resilient member '67 is bent at a right angle and forms a sleeve which bears against the outer surface of the intermediate part of the shield 70 and is disposed at the vicinity of the inner periphery of the annular flange 64. The leg opposite leg 72 of the U-shaped part 68 of the resilient member 67 extends radially inward and is formed with an edge portion or bead 713 which resiliently flexes and fits snugly against a shoulder formed at one end of the shell of the motor 126 b.

The annular flange 64 is carried by the outwardly extending part 69 of the shield 70 and disposed about the intermediate part thereof. As shown in FIG. 6, the annular flange 64 is formed with openings which threadingly receive screws 73', the heads of which bear against a bearing plate 74 provided at one face of the U-shaped part 68 of the resilient member 67.

The wall part 6 3 has a large central opening through which the motor-fan unit 126 can be moved. As shown in FIG. 5, the wall part 63 forms a rim which at the inner peripheral edge portion thereof, is provided with notches or recesses 75 which are spaced apart from one another to form a plurality of circumferentially interspaced projections and indentations. The annular member 64 is provided with outwardly projecting parts or projections 64a which are spaced from one another to form a plurality of circumferentially interspaced projections and indentations. v

When the projections 64a are directly in front of and in axial alignment with the recesses 75 in the wall part 63, the annular flange 64 can be moved axially of the inner wall 128 and pass through the central opening in the rim 63. When the motor-fan unit 126 is being mounted in position in this manner and thereafter turned angularly about an axis extending axially of the inner wall 128, the projections 64a on the annular flange 64 be come wedged against the peripheral edge portion 63' of the wall part or rim 63 which are disposed between the notches or recesses 75. With this construction the annular flange 74 and rim 63 coact and cooperate to form a slip-clamp type of connection for mounting the motorfan unit 126 resiliently in position within the inner wall 128, Thereafter, the screws 73 are tightened to secure the motor-fan unit 126 rigidly in position.

The disclosure in the aforementioned Faith-Ell patent may be considered as being incorporated in this application, and, if desired, reference may be made thereto for a detailed description of the structure for resiliently mounting the motor-fan unit 126 within the compartment 121.

When the vacuum cleaner is being operated and the fan 126a driven by the shaft 126k of the motor 126b, dust laden air is drawn through the suction hose into the interior of the casing 110 through the air inlet opening 137b in the cover 137. Dust collects in the dust bag 127 and air free of such dust passes through the dust bag into the bottom of the compartment 122. The compartments 121 and 122 are separated by a partition 76 which includes portions of the inner walls 128 and 129 and a portion of the foamed plastic body 111. The partition 76 is formed with an opening 77 defining a passageway 123 through which air can flow from the bottom of the &

compartment 122 into the bottom of the compartment 121. An apertured grid 78, which is curved at one side and flat on its opposite side and may be formed of rigid plastic, is fixed at its corners at 79, as by riveting, for example, to the inner wall 129. Air introduced into the compartment 121 passes into the inlet 126a of the fan 126a. The air is discharged from the fan 126 and flows through the motor 126b to effect cooling thereof, such .air passing from the motor at 80.

Spaced ribs 81' and 32 are provided at the inside of the closure member 140 Within the areas defined by the flanges 14611 and 1400. The ribs 81' and 82 are perpendicular to that flat bottom 140s and are parallel to the axis of the passageway 123 extending between the bottoms of the compartments 121 and 122. The ribs 81' at the bottom of the compartment 122 promote changing the direction of air flow from the compartment 122 into the passageway 123, and the ribs 82 at the bottom of the compartment 121 promote changing the direction of air flow from the passageway 123 into the compartment 121. Further, the ribs 81' and 82 tend to reduce the formation of eddy currents at the bottoms of the compartments 121 and 122.

The resilient member 67 and the rim or stationary wall part 63 define a seal between the motor 126]) and inner wall 128 which blocks flow of air past the exterior of the motor. With such a seal all of the air drawn into the fan 126a is directed through the motor 126b and discharged therefrom at at the commutator end of the motor, for example. It will now be understood that the vacuum cleaner just described includes the inner wall 129 which defines a suction passageway in which the dust bag 127 is positioned. The inner wall 128 defines the compartment 121 for the motor-fan unit 126. Further, the top part of the compartment 121 functions as an exhaust passage 121a. The exhaust passage extends upward from the seal formed by the resilient member 67 and rim 63 to an opening 134' in the plate 50 through which air is discharged from the vacuum cleaner. The structure providing the exhaust passage 121a, which is defined in part by the partition 76, is at one side of the inner Wall 129 defining the suction passageway 122.

As in the first described embodiment, the housing may be provided with rings or loops 119 to which straps of a shoulder harness may be fastened, Rings or loops 112 also may be fixed to the backing plates 50 and 51 to which the straps 120 of the harness may be fastened, as shown in FIGS. 4 and 5. The foamed cellular plastic body 111 may be formed in situ and is of a type that adheres very strongly to the surfaces of the outer wall 112 and inner walls 128 and 129. Foamed plastic of this kind completely fills the space between the outer and inner walls to provide a housmg or shell which is self-sustaining and semi-rigid and possesses significant mechanical strength to support and hold the inner walls 128 and 129 in position within the outer wall 112.

When the plastic body 111 is foamed in situ, the outer wall 112, which may be formed of plastic and is flexible, may be positioned against the inner surface of a hollow for-m defining the shape of the vacuum cleaner housing 110. The inner walls 128 and 129 of cylindrical form are positioned within such hollow form by suitable jigs and end plates may be positioned against the end-s of the hollow form and the inner walls 128 and 129. The top plate may be provided with an opening through which the foamable plastic material, such as polyurethane plastic, is introduced. The resulting foamed plastic completely fills the space between the outer flexible wall 112 and inner walls 128 and 129 to form the foamed cellular plastic body 111 which functions to stretch the outer wall 112 so that it completely envelope the foamed plastic body and is smooth and free of wrinkles. When foaming of the plastic body is taking place, the space between the outer and inner walls becomes completely filled with the foaming material and in the final stage of foaming a quantity of the foamed plastic flows through the filling opening in the top plate. After the foamed plastic has set and hardened, the end plates are removed and the plastic body is trimmed at the top and bottom of the inner and outer walls. The foamed cellular plastic body 111 formed in situ in the manner just explained will adhere very strongly to the inner surface of the outer wall 112 and to the outer surfaces of the inner walls 128 and 129 which, as explained above in describing the embodiment of FIGS. 1 to 3, is semi-rigid. The angle members 52 and 52' are so positioned on the inner walls 128 and 129 that the radially extending arms thereof, which are formed with the threaded openings 54 and 54' to receive the cap screws 55, are essentially flush with the top and bottom surfaces of the foamed plastic body 111, as explained above.

In view of the foregoing, it will now be understood that a vacuum cleaner casing or housing has been provided having spaced outer and inner walls defining a U-shaped air passage, the motor-fan unit 126 and dust bag 127 being disposed in the long arms of the U. The motor-fan unit 126 is mounted on the inner wall 128 of one long arm of the U. The space between the inner walls 128 and 129 and the outer wall 112 is completely filled with foamed cellular plastic 111 which is semirigid and possesses significant mechanical strength and at the same time will provide a vacuum cleaner which is extremely light and can readily be carried from place to place. Due to the fact that the foamed plastic body 111 is semi-rigid, the outer wall 112 will yield and move inward slightly responsive to physical force applied to its outer surface.

While several embodiments of the invention have been shown and described, such variations and modifications are contemplated which fall within the true spirit and scope of the invention, as pointed out in the following claims.

I claim:

1. A suction cleaner having a casing provided with an air inlet and an air outlet and a dust bag and a motor-fan unit therebetween, the casing comprising first and second ends and an outer side wall of annular form therebetween, the air inlet and air outlet being at the first end of the casing, means defining a U-shaped air passageway within the casing which includes a closed end at the second end of the casing and a pair of spaced elongated arms which extend from the closed end of the air passageway toward the first end of the casing and terminate at the air inlet and air outlet, respectively, at the first end of the casing, each of the elongated arms including a hollow member, the hollow members being spaced from one another and from the outer side wall of the casing and extending between the first and second ends of the casing, means for positioning the dust bag within the hollow member of one arm of the U-shaped passageway which terminates at the air inlet, means for mounting the motor-fan unit within the hollow member of the other arm of the U-shaped passageway which terminates at the air outlet, a body of semi-rigid foamed plastic which completely fills the space between the outer side wall of the casing and the hollow members and the space between the hollow members and functions to permanently anchor and position the hollow members within the outer side wall of the casing, the hollow arms being separated from one another by a partition which includes a portion of each of the hollow members and a portion of the foamed plastic body which is disposed therebetween, the partition having an opening at the second end of the casing which defines the closed end of the U-shaped passageway, the casing at the first and second ends including end closures each having an outer flange and a pair of spaced inner flanges of annular form, the outer flanges telescopically fitting over the outer side wall at opposite ends of the hollow members and the inner flanges of each of the end closures telescopically fitting within the end 10- of a dilferent one of the hollow members at each end of the casing.

2. A suction cleaner as set forth in claim 1 which includes means for detachably connecting the end closures to the ends of the hollow members, the detachable connecting means comprising parts which are fixed to the hollow members and include portions which project radially outward therefrom and are flush with the surfaces of the foamed plastic body.

3. A suction cleaner as set forth in claim 2 which includes backing plates bearing against the outer surfaces of the end closures, the detachable connecting means functioning to connect both the plates and the end closures to the ends of the hollow members.

4. A suction cleaner as set forth in claim 3 in which both the end closure and backing plate at one end of the foamed plastic body, at the closed end of the U- shaped passageway, are imperforate and both the end closure and backing plate at the opposite end of the plastic body, at the first end of the casing, are apertured, the apertured end closure having a pair of openings each of which is in communication with a different end opening of the hollow members at the first end of the casing, the hollow member of the one arm in which the dust bag is positioned defining a dust bag compartment and the hollow member of the other arm in which the motor-fan unit is mounted defining a motor-fan unit compartment, the apertured backing plate having openings one of which communicates with the dust bag compartment and the other of which communicates with the motor-fan unit compartment, and a removable top cover which closes the opening in the backing plate that provides access to the dust bag compartment.

5. A suction cleaner having a casing provided with an air inlet and an air outlet and a dust bag and a motorfan unit therebetween, the casing comprising first and second ends and an outer side wall of annular form therebetween, the air inlet and air outlet being at the first end of the casing, means defining a U-shaped air passageway within the casing which includes a closed'end at the second end of the casing and a pair of spaced elongated arms which extend from the closed end of the air passageway toward the first end of the casing and terminate at the air inlet and air outlet, respectively, at the first end of the casing, each of the elongated arms including a hollow member, the hollow members being spaced from one another and from the outer side wall of the casing and extending between the first and second ends of the casing, means for positioning the dust bag within the hollow member of one arm of the U-shaped passageway which terminates at the air inlet, means for mounting the motor-fan unit within the hollow member of the other arm of the U-shaped passageway which terminates at the air outlet, a body of semi-rigid foamed plastic which completely fills the space between the outer side wall of the casing and the hollow members and the space between the hollow members and functions to permanently anchor and position the hollow members within the outer side wall of the casing, the hollow arms being separated from one another by a partition which includes a portion of each of the hollow members and a portion of the foamed plastic body which is disposed there between, the partition having an opening at the second end of the casing which defines the closed end of the U-shaped passageway, the casing including end closure members and means for detachably connecting the closure members to the ends of the hollow members, the closure member at one end of the foamed plastic body, at the closed end of the U-shaped passageway, being imperforate, the closure member at the opposite end of the foamed plastic body being apertured and having at least two openings each of which is in communication with a different elongated arm of the U-shaped passageway, and the inside of the closure member at the closed end of the U-shaped passageway having ribs which project into References Cited by the Examiner UNITED STATES PATENTS 1,765,784 6/1930 Aldinger 15-326 1,787,646 1/1931 Smith 15-327 2,281,858 5/ 1942 Pierce 15-326 10 2,372,007 3/1945 Kroenlein v 55-467 2,392,205 1/ 1946 Wales 55-4-71 2,504,487 4/1950 Anson 15-507 2,552,641 5/1951 Morrison 220-9 2,583,949 1/ 1952 Kendrick 55-467 2,688,379 9/1954 Anderson 55-472 X 2,843,315 7/1958 Faith-Ell 230232 12/ 1958 Lachowicz 55-472 6/1961 Lindsjo et al. 230232 7/1962 Latferty 264-53 7/ 1962 Harrison 264-51 10/ 1962 Beyer et a1 264-47 5/ 1963 Andersson-Sason 15-327 FOREIGN PATENTS 9/ 1957 Australia. 4/ 1952 France. 2/ 1937 Great Britain. 11/ 1955 Great Britain. 5/1-9'59 Great Britain.

15 HAR-RY B. THORNTON, Primary Examiner.

B. NOZICK, Assistant Examiner. 

1. A SUCTION CLEANER HAVING A CASING PROVIDED WITH AN AIR INLET AND AN AIR OUTLET AND A DUST BAG AND A MOTOR-FAN UNIT THEREBETWEEN, THE CASING COMPRISING FIRST AND SECOND ENDS AND AN OUTER SIDE WALL OF ANNULAR FORM THEREBETWEEN, THE AIR INLET AND AIR OUTLET BEING AT THE FIRST END OF THE CASING, MEANS DEFINING A U-SHAPED AIR PASSAGEWAY WITHIN THE CASING WHICH INCLUDES A CLOSED END AT THE SECOND END OF THE CASING AND A PAIR OF SPACED ELONGATED ARMS WHICH EXTEND FROM THE CLOSED END OF THE AIR PASSAGEWAY TOWARD THE FIRST END OF THE CASING AND TERMINATE AT THE AIR INLET AND AIR OUTLET, RESPECTIVELY, AT THE FIRST END OF THE CASING, EACH OF THE ELONGATED ARMS INCLUDING A HOLLOW MEMBER, THE HOLLOW MEMBERS BEING SPACED FROM ONE ANOTHER AND FROM THE OUTER SIDE WALL OF THE CASING AND EXTENDING BETWEEN THE FIRST AND SECOND ENDS OF THE CASING, MEANS FOR POSITIONING THE DUST BAG WITHIN THE HOLLOW MEMBER OF ONE ARM OF THE U-SHAPED PASSAGEWAY WHICH TERMINATES AT THE AIR INLET, MEANS FOR MOUNTING THE MOTOR-FAN UNIT WITHIN THE HOLLOW MEMBER OF THE OTHER ARM OF THE U-SHAPED PASSAGEWAY WHICH TERMINATES AT THE AIR OUTLET, A BODY OF SEMI-RIGID FOAMED PLASTIC WHICH COMPLETELY FILLS THE SPACE BETWEEN THE OUTER SIDE WALL OF THE CASING AND THE HOLLOW MEMBERS AND THE SPACE BETWEEN THE HOLLOW MEMBERS AND FUNCTIONS TO PERMANENTLY ANCHOR AND POSITION THE HOLLOW MEMBERS WITHIN THE OUTER SIDE WALL OF THE CASING, THE HOLLOW ARMS BEING SEPARATED FROM ONE ANOTHER BY A PARTITION WHICH INCLUDES A PORTION OF EACH OF THE HOLLOW MEMBERS AND A PORTION OF THE FOAMED PLASTIC BODY WHICH IS DISPOSED THEREBETWEEN, THE PARTITION HAVING AN OPENING AT THE SECOND END OF THE CASING WHICH DEFINES THE CLOSED END OF THE U-SHAPED PASSAGEWAY, THE CASING AT THE FIRST AND SECOND ENDS INCLUDING END CLOSURES EACH HAVING AN OUTER FLANGE AND A PAIR OF SPACED INNER FLANGES OF ANNULAR FORM, THE OUTER FLANGES TELESCOPICALLY FITTING OVER THE OUTER SIDE WALL AT OPPOSITE ENDS OF THE HOLLOW MEMBERS AND THE INNER FLANGES OF EACH OF THE END CLOSURES TELESCOPICALLY FITTING WITHIN THE END OF A DIFFERENT ONE OF THE HOLLOW MEMBERS AT EACH END OF THE CASING. 